Wang Ming, Zhu Xiao-Yang, Wang Liang, Lin Yu
Department of Radiation Therapy, Cangzhou Central Hospital, Cangzhou, Hebei Province, China.
PLoS One. 2013 Oct 9;8(10):e76915. doi: 10.1371/journal.pone.0076915. eCollection 2013.
Several observational studies have investigated the association between -607 C/A polymorphism of IL-18 gene and cancer risk; however, the results were inconsistent. Therefore, we performed a meta-analysis to derive a more precise estimation of the association to help us better understand the relationship between -607 C/A polymorphism of IL-18 gene promoter and risk of cancer.
A literature search was carried out using PubMed, EMBASE, and China National Knowledge Infrastructure (CNKI) database between January 1966 and February 2013. Fixed-effect and random-effect models were used to estimate the pooled odds ratio (OR) and the corresponding 95% confidence intervals (CIs).
A total of 22 case-control studies including 4100 cancer cases and 4327 controls contributed to the analysis. Significant association between -607C/A polymorphism in IL-18 gene promoter and cancer risk was observed (CA vs CC:OR =1.221, 95% CI: 1.096, 1.360; P(heterogeneity)=0.219; AA/CA vs. CC:OR =1.203, 95% CI: 1.057, 1.369; P(heterogeneity)=0.064). In the subgroup analysis by ethnicity, -607C/A polymorphism significantly increased risk of cancer among Asian population (AA/CA vs. CC:OR =1.197, 95% CI: 1.023,1.401; P(heterogeneity)=0.088); however, no significant association was found in Caucasian or African population. The -607C/A polymorphism was associated with a significantly increased risk of nasopharyngeal carcinoma (CA vs CC:OR =1.330, 95% CI: 1.029,1.719; P(heterogeneity)=0.704; AA/CA vs. CC:OR =1.323, 95% CI: 1.037,1.687; P(heterogeneity)=0.823) and esophageal cancer (AA/CA vs. CC:OR =1.289, 95% CI: 1.002,1.658; P(heterogeneity)=0.700).
The present meta-analysis suggests that the -607C/A polymorphisms in IL-18 gene promoter is associated with a significantly increased risk of cancer, especially for nasopharyngeal carcinoma and esophageal cancer and in Asian population. More studies with larger sample size, well controlled confounding factors are warranted to validate this association.
多项观察性研究探讨了白细胞介素-18（IL-18）基因-607 C/A多态性与癌症风险之间的关联；然而，结果并不一致。因此，我们进行了一项荟萃分析，以更精确地估计这种关联，从而帮助我们更好地理解IL-18基因启动子-607 C/A多态性与癌症风险之间的关系。
利用PubMed、EMBASE和中国知网（CNKI）数据库在1966年1月至2013年2月期间进行文献检索。采用固定效应和随机效应模型估计合并比值比（OR）及相应的95%置信区间（CI）。
共有22项病例对照研究纳入分析，包括4100例癌症病例和4327例对照。观察到IL-18基因启动子-607C/A多态性与癌症风险之间存在显著关联（CA与CC比较：OR =1.221，95%CI：1.096，1.360；异质性P=0.219；AA/CA与CC比较：OR =1.203，95%CI：1.057，1.369；异质性P=0.064）。在按种族进行的亚组分析中，-607C/A多态性显著增加了亚洲人群患癌症的风险（AA/CA与CC比较：OR =1.197，95%CI：1.023，1.401；异质性P=0.088）；然而，在白种人或非洲人群中未发现显著关联。-607C/A多态性与鼻咽癌风险显著增加相关（CA与CC比较：OR =1.330，95%CI：1.029，1.719；异质性P=0.704；AA/CA与CC比较：OR =1.323，95%CI：1.037，1.687；异质性P=0.823）和食管癌（AA/CA与CC比较：OR =1.289，95%CI：1.002，1.658；异质性P=0.700）。
本荟萃分析表明，IL-18基因启动子-607C/A多态性与癌症风险显著增加相关，尤其是鼻咽癌和食管癌，以及在亚洲人群中。需要更多样本量更大、混杂因素控制良好的研究来验证这种关联。
